The invention relates to a steam power plant, comprising essentially a steam generator, a turbo group with condensation steam turbine and generator, a water-cooled condenser, and a bleeder steam-heated pre-heater system.
Such power plants are usually produced according to customer specification and site requirements and therefore involve lengthy project development, planning, and construction times and, as a result, high costs. Especially the construction time in these customer specification-oriented power plants is influenced by the fact that a very detailed advance engineering is not possible, and essential aspects of the work, for example the construction portion, which should be processed as early as possible, only can be started with a delay.
It is known per se to reduce the construction time by building power plants using open air construction. But this type of construction again causes a number of disadvantages with respect to their operation as well as maintenance and repair. In this connection, DE 1426918 A1 discloses the concept of a steam power plant designed to be built in a shorter construction time and reduced investment costs, and which is supposed to hereby reduce said disadvantages. This concept is essentially based on the fact that the turbo group is arranged in a lane between the steam generators and a portal crane is mounted on the steam generators in order to facilitate both their assembly as well as the assembly of the turbo group. In addition, the principle of multipurpose use has been realized in such a way that the support frames of the steam generator or the coal bunker are at the same time equipped for receiving secondary installations, and the portal crane is able to serve both steam generator and power generator parts. The steam power plant constructed according to this concept is very compact and is brought together within a tight outline. The main emphasis of this solution is the reduction of construction time and expenditures. The price for the advantages of a small space requirement and multipurpose use of support frames is a vertical arrangement of numerous installation parts. But it is especially this vertical arrangement of numerous installation parts whose assembly is facilitated with the highly positioned portal crane during the construction phase, that excludes a use of the crane for necessary repair and maintenance purposes of the same installation parts in the operation phase. After the construction phase, the crane ""s use is essentially limited to the turbo group, since it is unable to access the installation parts of all intermediate planes.
The invention is designed to remedy this problem. Starting with the mentioned state of the art, the invention is based on the objective of creating a steam power plant characterized by very friendly maintenance and repair friendliness. In addition, a steam power plant should be created that achieves substantial standardization and can be built at a variety of possible sites.
The invention therefore is based on a steam power plant comprising essentially a steam generator, a turbo group with condensation steam turbine and generator, a water-cooled condenser, and a bleeder steam-heated pre-heater system and a portal crane and is characterized in that all components of the steam power plant, including the fuel storage site, are located at ground-level and placed in an open air arrangement and the portal crane swings over an area in which the turbo group with the condenser, pre-heater system and associated pumps as well as the transformers are arranged.
If the steam generator, flue gas cleaning system and chimney are located in series within a common flue gas axis, it is useful that the turbo group is located immediately adjacent and parallel to them.
If the fuel storage site is a coal heap, it would be suitable to locate it down-windxe2x80x94seen in the main wind directionxe2x80x94behind the turbo group and steam generator.
The advantage of all these measures is in particular that the standardization of the installation engineering and of the components reduces the investment costs to a remarkable degree. The outline of the power plant is formed by a clearly defined rectangle. This makes it possible to expand the installation at any time by simply placing such rectangles next to each other. The previously common, very extensive project engineering is no longer required hereby. The power plant blocks that will be located next to each other are identical; only the access roads must be minimally adapted. Another advantage is the consistently realized open air placement. This makes it possible to forego the expensive and time-consuming construction of buildings, such as boiler and machine house. The measure of arranging the turbo group with the condenser, pre-heater system and associated pumps, as well as with at least the own-demand transformers in such a way that a portal crane can swing over them also defines a rectangular cross-section for these components. This makes it possible to arrange the installation parts in the tightest space directly next to each other without negatively affecting operation and maintenance. Maintenance and repair work can be performed with the crane. This arrangement also enables the shortest possible connections between the various installation parts, which again has a positive effect on assembly and maintenance.
The sensible measure of locating the coal heap down-wind behind the turbo group and the steam generator in no way has an adverse effect on the requirement of a rectangular cross-section of the installation and can be performed independently from the wind direction. This makes it possible to avoid coal dust emissions in the area of the technical installations and administrative operations. The desired rectangular cross-section in any case can also be realized in relation to the geographical location of the body of water necessary for cooling purposes. The respective situation plan in each case naturally takes into account this water location, whereby the emphasis here is also on the shortest possible connection paths.
A flatbed feeder located at ground level is provided for depositing the unground coal onto the inclined belt to the coal breaker. This means that the large and deep, concrete-lined, subterranean feeder pit that usually was required up to now is no longer necessary, which greatly reduces civil engineering work.
The steam generator is preferably supplied with roughly ground coal from coal silos. It is hereby reasonable that the coal silos associated with the steam generator are connected with the coal breaker located upstream from the steam generator by an at least approximately horizontally extending conveyor device with subsequent vertical conveyor device. The ground-level placement of the horizontally extending conveyor device makes it possible to eliminate complicated steel frames.
The steam turbine has an axial exit so that the steam condenser is located in the axial extension of the steam turbine. This solution, which is advantageous because of the almost ground-level placement of the turbo group, as well as the open air placement, allows unlimited access to the condenser. If condenser pipes must be replaced, this does no longer require removal facade elements from a building, as was the case in the past. In addition, the portal crane swinging over the condenser can be used for such maintenance procedures.
It is advantageous if all pre-heaters are designed for the same pressure on their water side, have essentially the same dimensions, and are located adjacent to the turbo group. This measure guarantees the shortest connections both on the water and steam side and also allows use of the portal crane for maintenance work.
Starting with the recognition that because of lacking advance planning and customization to client specifications the construction time for a power plant is extraordinarily long today, the invention, as characterized in the claims, is based on the task of achieving substantial standardization and creating a power plant that can be built at a variety of possible sites.